1. Field of the Invention:
The invention relates to tooth positioning appliances, and in particular to an appliance to be used with deciduous dentition or mixed dentition to expand the posterior segments.
2. Description of the Prior Art:
Over crowding of the teeth, particularly the anterior teeth is one condition which can be corrected with orthodontic treatment. Oftentimes metallic bands and wires are used in the permanent dentition stage to provide the desired spacing. There have also been provided devices such as my prior device disclosed in U.S. Pat. No. 4,139,944 in which a plastic removable positioner is provided for use in correcting certain conditions in a permanent or mixed dentition stage.